Explosive



May 21, 1963 H. G. REUTHER EXPLOSIVE Filed Feb. 3, 1948 3 Sheets-Sheet 1/GH VLOC/TY HIGH INTENSITY WAVES LOW VELOCITY LOW INTENSITY WAVES HIGHVELOCITY HIGH l/VDENS/T)" WA V55 LOW VELOCITY LOH] INTENSITY WAVES Habar? @3811, Mar

allozncqa y 1963 H. G. REUTHER 3,090,306

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Huber? 6f Reufher 3,090,306 Patented May 21, 1963 3,090,306 EXPLOSIVEHubert G. Reuther, Ell: Club, 2828 Kalkaua Ave, Honolulu, Hawaii FiledFeb. 3, 1948, Ser. No. 6,105 2 Claims. (Cl. 102-22) (Granted under Title35, US. Code (1952), see. 266) The present invention relates to militaryexplosives designed primarily to detonate mines of a subterranean minefield by impacts of concussion waves produced by the detonation of anabove-ground explosive charge.

It has been observed in practice that the individual mines of asubterranean mine field may be detonated effectively by impact on theground of percussion waves of sufficiently high intensity, which wavesmay be produced by the detonation of an explosive charge held at apredetermined distance above the ground.

It has been found that the efiiciency of the detonation of buried landmines by such percussion waves is much increased when the waves arecontrolled in a predetermined restricted pattern.

In accordance with the present invention there are provided improvedexplosive charges for the above-indicated purposes wherein there iseffected a predetermined con trol of percussion waves and attendantpattern on the area of the explosive forces from the charge, theexplosion Waves forming a component pattern of high and low velocity andintensity Waves wherein the latter are enveloped and given direction bythe former. In accordance with the invention there is produced a highpressure encircling cone which has its apex near the point ofdetonation, thereby confining the enclosed shock waves to a restrictedarea. This in turn causes an even distribution of pressure inside theencircling area. This area can be controlled at will by varying therelation of the lower cone angle with the ground. It also utilizes theunused forces projected from the side and directs them earthward atright angles to the lower cone, and these can he in any number of sidesfrom triangular to a circular cone.

As has been indicated above, the improved effects produced by thepresent invention may be obtained either by producing a higher speedencircling outer cone confining the shock or pressure wave inside of thecone over a given distributed area, by putting explosive materials ofhigh combustion rate in the top portion of a charge having a doubleconical shape, and an explosive having a lower rate of combustion in thebottom portion of the charge, or by a suitable shape of a charge ofhomogeneous composition, or by a combination of a particular shape ofthe charge coupled with explosive materials having different rates ofcombustion, as will be pointed out in detail hereinafter.

Generally speaking, the improved results of the present invention areobtained by enclosing detonation waves of relatively low magnitude orspeed in an enveloping high intensity or high-speed wave envelope, whichenvelope and enclosed waves are directed to the objective by theparticular shape of the charge itself. That is to say, the results ofthe improvements of this invention are obtained by exploding upper andlower charges, the lower charge, that is, the one closer to the ground,having less detonating effect than the upper charge. The explosiveforces resulting from the upper charge control the area in which theexplosive forces of the lower charge are confined. The charge of thepresent invention creates a conical or polygonal umbrella, limiting thedispersion of the second charge. The effect of the upper charge is tocreate a hollow cone or annulus of forces, which would restrict theexpansion of the upper cone, thereby driving a higher speed encirclingouter cone confining the shock or pressure inside of the cone or byshaping the charge into the indicated at 26, for reception cones, oneperpendicular to the vertical and the other parallel to the horizontalon the outer face of the lower cone. The length of the outer surfacewalls of the charge affect the direction of the forces from theexplosion. The longer the outer sunfiace, the greater total force fromthat surface, and the shorter the length of the outer surface, thesmaller the total force, the two together combining to form a resultantforce from the charge.

The invention will be understood more readily lirorn a consideration ofthe accompanying drawings, wherein:

FIGURE 1 represents a side elevation of one form of charge shaped toproduce the effects of the present invention;

FIGURE 2 is a sectional elevation through the vertical axis of FIGURE 1;

FIGURE 3 is a diagrammatic showing of the manner in which the explosionWaves resulting from the explosion of the charge in FIGURES l and 2 arecontrolled by the shape of this charge and directed on to a subterraneanmine field;

FIGURE 4 is an isometric view of a modified form of charge;

FIGURE 5 is a sectional elevation of the charge of FIGURE 4, taken alongthe vertical axis of FIGURE 4;

FIGURE 6 is a plan view showing the ground pattern obtained by thefiring of the charge of FIGURE 4;

FIGURE 7 is a diagrammatic view, similar to FIGURE 3, but showing thecontrol obtained by the modification of FIGURE 4; 1

FIGURE 8 is a perspective view of a still further modification, usingexplosive charges having differential rates of combustion;

FIGURE 9 is a sectional elevation of the modification of FIGURE 8 takenalong the vertical axis of FIGURE 8, the view showing diagrammaticallythe initiation of explosive waves propagated by the explosion of thecharge of FIGURE 8, at the instant of explosion;

FIGURE 10 is an explosion diagram showing the effects of the explosionof the charge of FIGURE 8;

FIGURE 11 is a perspective view of a further modified form of anexplosive charge producing the results of the lnvention;

FIGURE 12 is a vertical sectional elevation taken along the verticalaxis of the charge of FIGURE 11; and

FIGURE 13 is an explosion diagram showing the control of the explosivewaves propagated by explosion of the charge of FIGURE 12.

It will be understood that the charges in each instance are enclosed ina suitable casing, not shown, which is provided with means forsuspending the charges above the mine field to be detonated, at a heightrequisite for maximum eliectiveness of detonation of the buried mines.

Referring more particularly to the drawings, and first to FIGURES l, 2and 3, the illustrated charge comprises a truncated, molded, conicalportion 12, having a fiat, truncated surface 14 and a base 16. Thecharge also has a wide conical portion 18 with a base 20 aligned withthe base 16 of the conical portion 12, the bases 16 and 20 beingspacedly connected by a cylindrical portion 22. The height of theconical portion 18 is approximately fifty percent greater than is theheight of frusto-conical portion 12, both portions 12 and 18 being rightangle cones. A priming charge 24 is shown as inserted in the conicalportion 12, the priming charge being recessed, as of an electrical lead,not shown, for the provision of a detonating spark. The conical portion18 terminates in a wide apex 28 and, in use, the charge is suspendedfrom a suitable mounting means not shown at a desired predetermineddistance above a mine field 30 for detonation of the mines 32 3 thereof,and when the charge is detonated, a wave pattern such as is indicated inFIGURE 3 is obtained.

In this diagram of FIGURE 3, heavy or concentrated percussion waves arepropagated in all directions, including downwardly, in conformity withthe angle of slope of the lower cone IS, the slope of the lower coneprogressively reducing the amount of the explosive charge in a givenvolume. Hence, the waves 34 propagated from the apex 23 of the lowercone I8 are of less intensity than are the waves 36 propagated from theportions of the cone adjacent to the base, and such waves are enclosedand enveloped by the high intensity outside waves and are directedthereby onto a localized area of the mine field 3th, the extent of whicharea is dependent upon, and controlled by, the angle of slope of thelower cone I8, to the vertical axis of the charge.

In FIGURES l, 2 and 3 the charge is a molded charge of uniformcomposition which is not critical, but may be molded trinitrotoluene,for example, also, where the charge is detonated electrically, thepriming charge 24 actually is optional, but it is preferred to assuresmooth explosion of the charge.

FIGURES 4 through 7 show a different form of charge operating on asimilar principle to the charge of FIG- URES l, 2 and 3, except insteadof being conical, the charge is pyramidal in shape. The truncatedpyramidal upper charge portion 40 has a fiat truncated surface 42 andbase 44. The lower pyramid 46 has a base 48 and terminates in apex 50.Base portions 44 and 48 are in registry, but are spaced by a narrow,substantially rectangular band 52. As shown in FIGURE 5, the height ofthe lower pyramid 46 is approximately twice that of the upper truncatedpyramid 49. This modification produces wave propagation similar to thatshown in FIG- URE 7, wherein the waves 54 of high intensity from thesides of the pyramid 46 enclose the waves 56 of lower intensity producedfrom the apex 50 of the pyramid, the waves 56 being limited and guidedby the high intensity and velocity waves 54, the angular direction ofwhich is determined by the slope of the pyramid 46. FIGURE 6 shows adiagrammatic representation of the ground pattern produced by thedetonation of this charge, which pattern acts as confirmation of thediagram of FIGURE 7. It will be seen from FIGURE 6 that the outline 58of the pattern is formed by the intersection of the high velocity, highintensity waves 54 with the ground, producing the substantially squareoutline 58 corresponding to the square base 48 of the pyramid 46, thediagonals 60 and 62 representing the intersecting edges of the pyramid46, the intersection 64 of the diagonals 60 and 62 corresponding to theapex 50 of the pyramid '46. Highly effective detonation of the mines 66is obtained.

Like the precedingly described modification of FIG- URES 1 and 2, theembodiment of the invention shown in FIGURES 4 and may be of uniformcomposition, for instance trinitrotoluene, provided with a primingcharge 63, recessed at 70 for reception of an electric fiiring lead, notshown.

The modification of FIGURES 8 and 9 is similar to the modification ofFIGURES 1 and 2. The truncated cone 61 is of a composition that has asubstantially higher rate of combustion than the full conical portion 63of the lower cone 65, the truncated cone, therefore, being a relativelyhigher explosive than portion 63, the relative amounts of the twocompositions being about as shown in FIGURE 9, the composition of thetruncated cone 61, occupying also upper portions of the lower cone 6'5.The truncated surface 67 is provided with the priming charge 71, whichis recessed as shown at 72 for the reception of a firing lead, notshown. The particular explosive compositions are dependent upon the use,the requirement in this case being a substantial differential in thespeed and volume of the wave propagation from the different explosivecharges. For example, the higher explosive charge may be pentolite, forexample, with a 50-50 amatol combination for the lower explosive.

FIGURE 10 shows directive guidance of the slower interior waves 73 bythe enveloping high velocity waves 74, and directed on the mines 76.

FIGURES ll and 12 show an embodiment somewhat similar to that shown inFIGURES 8 and 9, and the operation is on the same principle resultingfrom the use of different explosive compositions having a substantialdifferential in combustion rates. The frusto-conical upper portion 1M ofthis embodiment has the flat truncated surface 166 thereon and containsthe priming charge 108, recessed at for reception of the firing lead,not shown. The base H2. of the upper frusto-conical portion 104 isaligned with the base 11.4 of the lower conical portion 116 through thecylindrical portion 118. The composition of the charge is the sameexcept for the portion 120 adjacent to the apex 122 of the cone.

FIGURE 13 shows the explosion diagram for this modification. Thelow-intensity waves of low velocity indicated at 124- are limited anddirected by the highintensity, high-velocity waves 126 and localizedover the mines 128.

In all of the forms of the invention herein illustrated and described,the control of the propagated waves is effected in either one of threemethods, i.e., (a) by pro gressively reducing the intensity of the wavesby progressive reduction of the explosive charge from maximum amount tominimum amount, the minimum amount being in an apex of a cone or pyramiddirected toward the ground, (b) by utilizing difierent explosivecompositions possessing differentials in the rate of combustion andhence wave propagation, the slower burning composition being locatedwithin the confines or boundaries (actual or projected) of the rapidlyburning composition, or (c) a combination of (a) and (b).

It will be observed also that, while the efiective waves are propagatedfrom the lower portions of each charge, it is desirable for maximumeffectiveness that the charges hang plumb from their suspensions and beas free as possible from oscillation. In each form there is an upwardlytapered section (truncated) and a lower section sloping to an apex in asymmetrical manner, surfaces in the upper and lower sections sloping inthe same direction being substantially parallel and forming an anglewith the base of approximately 45.

While it is shown on the drawings that the explosive waves from theupper truncated portions of the charges are dissipated and only thosefrom the lower sections are effective for the intended purpose,nevertheless, the tapered upper portion is found in practice to bedesirable, although not wholly necessary, as such increases stability ofthe charge while suspended for detonation and increases the directionaleffect and intensity of the downwardly directed waves, by controllingthe area in which the explosive forces of the lower charge are confined,propagation of all of which waves is in a direction normal to thesurfaces of the charge.

It is found in practice that the charges should be detonated so that theground pattern produced by each overlaps that produced by the succeedingcharges. It is found also in practice that the shapes of variouschargeschange their characteristic pattern in relation to their anglesand the angles and the mass of the charges. The length of the angles inrelation to each other and according to the mass and element of time ofcombustion of a charge has a pronounced effect in the dispersion andconcentration of the resulting explosion Waves when the charge is firedstatically above the ground. Any two or more angles produce a jet elfectcorresponding to their respective angles and length. From this factor acharge can be made to disperse or to concentrate into a crater caused bythe concentrated charge, the explosion waves from which can be confinedto the crater section as a shaped charge, or in a limited number ofconcentric circles. In

the case of the charge with the truncated pyramidal top and a pyramidallower inverted section (see FIGURES 4 and 5) the length of the angles ofthe lower section equal twice the length of the truncated top section,this causing a very pronounced jet effect from the four corners of thesquare formed by the bases of the top truncated section and the lowerpyramidal section. An unexpected result is observed in this connection,as most of the encasing material (a very light metal) becomesconcentrated in the four corners of the quadrangular figure on aparallel plane with the truncated top, as shown by the impact on theground (see FIGURE 6). This is found to be true when a line is projectedparallel to the hypotenuse of the truncated top. Where this linecontacts the ground, it designates the center of the crater thus formed.

From the foregoing, it will be apparent that initiation of combustion ofeach charge is adjacent to each of the enlarged base portions, andprogresses along the sloping body, uniformly progressively decreasingportions of the charge then undergoing combustion. In all forms, it willbe seen that the lower portion of the charge, that is, that which pointsto the ground, slopes uniformly from the enlarged base portion to theapex, and that is true whether the lower portion is conical or pyramidalin shape.

Having thus described my invention, what I claim as new and wish tosecure by Letters Patent is:

1. An explosive charge adapted to produce directionalized blast eifectscomprising a body including upper and lower body sections, a commonplanar base portion for the sections, the base portion having oppositeplanar surfaces from which the body sections converge oppositely, theupper body section terminating in a truncated surface paralleling saidplanar surfaces, the lower body section terminating in an apex, a sourceof detonation initiation mounted centrally of said truncated surface andsymmetrically with respect to the planar surfaces of the common baseportion, the source of detonation initiation producing upon detonation adetonation wave which,

passing through the body section in which detonation originated,impinges simultaneously all points of the planar base portion whereby anexplosive pattern consisting of high velocity, high intensity shockwaves, enclosing waves of lesser intensity and velocity, is propagatedby the body section opposite to that containing the source of detonationinitiation.

2. An explosive charge adapted to produce directionalized blast etfectsand comprising a homogeneous explosive composition including an upperbody portion, a lower body portion, and a planar base portion common tothe two body portions, the upper and lower body portions joining theplanar base portion and tapering oppositely therefrom, the upper bodyportion being truncated and the lower body portion terminating in anapex, means located centrally of the truncated portion of the upper bodyportion for initiating combustion of the charge, said lower body portionadjacent the planar base portion projecting explosive waves of highvelocity and intensity while said apex of the lower body portionpropagates explosive waves of less intensity and velocity, the shapedcharge being disposed relative to a surface receiving said explosivewaves so that the said waves are directed against the surface with thehigh velocity intensity waves enveloping the waves of less intensity andvelocity.

References Cited in the file of this patent UNITED STATES PATENTS

1. AN EXPLOSIVE CHARGE ADAPTED TO PRODUCE DIRECTIONALIZED BLAST EFFECTSCOMPRISING A BODY INCLUDING UPPER AND LOWER BODY SECTIONS, A COMMONPLANAR BASE PORTION FOR THE SECTIONS, THE BASE PORTION HAVING OPPOSITEPLANAR SURFACES FROM WHICH THE BODY SECTIONS COVERAGE OPPOSITELY, THEUPPER BODY SECTION TERMINATING IN A TRUNCATED SURFACE PARALLELING SAIDPLANER SURFACES, THE LOWER BODY SECTION TERMINATING IN AN APEX, A SOURCEOF DETONATION INITATION MOUNTED CENTRALLY OF SAID TRUNCATED SURFACE ANDSYMMETRICALLY WITH RESPECT TO THE PLANAR SURFACES OF THE COMMON BASEPORTION, THE SOURCE OF DETONATION INITIATION PRODUCING UPON DETONATION ADETONATION WAVE WHICH, PASSING THROUGH THE BODY SECTION IN WHICHDETONATION ORIGINATED, IMPINGES SIMULTANEOUSLY ALL POINTS OF THE PLANARBASE PORTION WHEREBY AN EXPLOSIVE PATTERN CONSISTING OF HIGH VELOCITY,HIGH INTENSITY SHOCK WAVES, ENCLOSING WAVES OF LESSER INTENSITY ANDVELOCITY IS PROPAGATED BY THE BODY SECTION OPPOSITE TO THAT CONTAININGTHE SOURCE OF DETONATION INITIATION.